14th Jun 2021, 21:05

My alternator regulator failed all of a sudden and without any warning. I got a battery light on the dash. The car would still drive on the battery alone but not for very long - it depends on the capacity and the charge of the battery. Generally speaking, when a battery starts having wear, it no longer gets charged to 100% so the alternator stays constantly at full power which can cause the regulator to overheat and fail all of a sudden - this happens especially if you rev hard the engine during a hot summer day. Always test see if the battery keeps a full charge of 12.7V-12.9V one hour after disconnecting it.

15th Jun 2021, 16:58

Good advice. Another sign of a bad alternator is dash lights on and off at random in the days leading up to failure. Most cars I had with a bad alternator did this; dash even lit up like a Christmas tree at one point. Next day would not start - battery was fine, but mechanic diagnosed a worn out alternator. Most are pretty expensive to replace, not sure which this car uses, but Bosch ones are dear but long lasting at least. Anything around 100K lifespan.

31st May 2022, 17:16

Have one just like this, and yes the Bosch alternators are good for around 100K. These are still very reliable cars; even today in 2022 I have a mk1 Octavia.

31st May 2022, 18:53

Also the mk1 and mk2 Octavia were so popular with taxi drivers that they had some cars long enough to anticipate its common faults, i.e. replacing certain parts before they failed.

I did hear of one Octavia taxi lasting till 500,000 miles!

1st Jun 2022, 22:34

Like these cars so much I bought another. Laurin Klement is the one to have, Elegance or SE models are next best, most Octavia's I have had in the past were Classic or S spec, try and avoid those if you can - early basic models didn't even have electric windows! A must for anyone these days surely.

Also to note regarding buying used Octavia's is avoid very high mileage cars - as already mentioned these cars were very popular as taxis! You can still find a good low mileage Octavia mk1 and mk2 if you look hard enough.